Several readers want me to know that Barack Obama is Irish. Just which part of Ireland his ancestors came from is, however, a vexed question, one that apparently has the shillelaghs a-swinging and the Guiness a-spilling over there.

He’s traced to Fulmuth Kearney, who sailed to New York from Ireland in 1850. But where in Ireland? The counties are feuding: One expert says Kearney was from Meath, another Carlow. Now comes the news of ties to County Offaly.

[Derb] I know only one joke that contains both Irish people and persons of color. Unfortunately, though not offensive in any really unpleasant way, it is deeply unsuitable for a respectable family website. Perhaps a few readers will enjoy a smile of recognition if I say that the last four words of the punch line are: “… was studded with diamonds.”